Manufacture of stove dampers



March 2, 1937. 4 M. L.- HUNKER 5 3 MANQ FA TURE OF iSTOVE DAMPERS ori inal Filed" April 8, 1935 2 Sheets-Sheet 1 March 2, 1937. M, L, HUNKER 2,072,304

I I MANUFACTURE OF STOVE D-AMPERS Original Filed April 8, 1955 2 Sheets-Sheet 2 LHwz/ie Patented Mar. 2, 1937 PATENT OFFICE.

MANUFACTURE OF STOVE DAMIPERS Martin 1 Hunker, Dover, Ohio, assignor to The Reeves Manufacturing Company, Dover, Ohio,

a corporationof Ohio Original application April 8, 1935, Serial No.

15,301, now"Patent No. 2,059,793, dated Novemher 3, 1936. -.Divided and this application July 15, 1935, Serial No. 31,500 i The invention relates to dampers. for stoves, particularlyadapted for use upon sheet metal heating stoves, and more especially to the manner in which the same are made, and this ap- 8" plication is a division of my copending application for Stove dampersiand manufacture of same, SerialNo. 15,301, filed April v8, 1935, issued as Patent No. 2,059,793, on November 3, 1936.

Dampers of the general type to which the invention pertains comprise a sheet metal plate or disk having a screw threaded stem fixed thereto and threaded intoi a stationary portion of the stove, a handle portion being provided at the outer end of the screw threaded stem for rotating the same so as to move the sheet metal plate or disk toward or away from the stove in order to close or uncover an opening in the stove through which air for combustion may be admitted.

In dampers of this general character the screw threaded stem is ordinarily in the form of a malleable iron casting, the sheet metal damper plate or disk being fixed thereto by upsetting an intermediate portion of the malleable iron stem to form lugs or shoulders which are pressed tightly down upon the damper plate, rigidly attaching the same to the stem.

It is also customary to form the handle upon the screw threaded stem by providing a pair of oppositely disposed axially alined arms upon the outer end portion of the stem to be grasped between the thumb and fingers in order to rotate the stem to adjust the position of the damper.

Malleable iron castings are expensive as compared with gray'iron castings and one object of the present improvement is to provide a damper of the character referred to which is so constructed that the screw threaded stem may be formed of a gray iron casting.

0 A further object is to provide a damper of this character comprising a screw threaded stem having two spaced shoulders near its outer end, the damper plate or disk being formed of sheet metal and having a central opening surrounded by an inwardly disposed annular flange, the sheet metal disk being attached to the threaded stem by springing said flange over one of said shoulders and then contracting the flange below said shoulder so as to tightly fix the damper plate upon the stem between the two shoulders.

; The above objects, together with others which will be apparent from the drawings and following description, or which may be later pointed 55 out, may be attained by constructing the improved damper in the manner illustrated in the accompanying drawings, in which Figure 1 is a rear or inner elevation of the improved damper and the casting by means of which it is connected to the stove;

Fig. 2, a front or outer elevation of the same;

Fig. 3, a vertical sectional view through the damper and casting shown in Figs. 1 and-.2;

Fig. 4, a sectional view through the dies by means of which the sheet metal damper plate or disk is attached to the threaded stem, the partsxof the. damper being shown in position for assembly; and

Fig. 5, a similar view showing the manner in which the assembly is completed.

Similar numerals refer to similar parts throughout the drawings.

The type of damper to which the invention pertains is especially adapted for use upon sheet metal heating stoves and for the purpose of mounting the damper upon the sheet metal side wall of the stove, a casting indicated generally at I0 is usually provided, this casting having a central opening H of sufiicient size to permit entrance to the stove of the desired amount of air for combustion and being attached to the sheet metal side wall of the stove as by rivets or the like located through the apertures l2 formed in the ears l3 of the casting. A spider or skeleton frame I4 may be located through the center of the opening II and provided with a central threaded aperture I5 through which the screw threaded stem 16 is adjustably located.

This screw threaded stem may be in the form of a gray iron casting and is provided near its outer end with the spacedshoulders l1 and I8, the latter being preferably of considerably greater diameter than the shoulder IT.

The stem I6 is preferably flared outward from the screw threaded portion to the shoulder IT, as indicated at l9, and the enlarged outer end portion of the stem between the shoulders I! and I8 is preferably conical or outwardly flared as shown at 20. At the outer end of the stem l6, beyond the shoulder I8, is formed a ball 2| provided with two oppositely disposed outwardly diverging arms 22.

The damper plate or disk 23 may be of sheet metal, preferably slightly conical in form as shown, the peripheral edge being curved inward as at 24 so as to tightly fit against the face of the casting II] when the damper is in closed position, as illustrated in Fig. 3. The damper plate 23 is provided with a central opening surrounded by the inwardly disposed annular flange 25 which is preferably inwardly tapered or frusto-conical as shown and which may be shouldered intermediate its ends as at 26.

In attaching the damper plate 23 to the threaded stem, the stem may be first seated in a die block 21 provided with a central bore 28 to receive the ball portion 2| of the handle of the stem and with the slots 29 to receive the arms 22.

The sheet metal damper plate 23 is then positioned upon the stem as shown in Fig. 4, the screw threaded portion of the stem being received through the central opening of the damper plate and the tapered inturned annular flange 25 of the damper plate resting upon the shoulder 11 of the stem.

The upper or movable die, which is in the form of a tube having a rounded lower edge 3|, is then moved downward around the screw threaded stem, the lower end thereof engaging the shouldered portion 26 of the annular flange 25, springing the flange over the shoulder IT, seating the shouldered portion 26 of the flange against the shoulder l8 of the stem and forcing the inner tapered end of the flange 25 around the portion 26 of the stem and beneath the shoulder [1 as shown in Fig. 5. When the tubular die 30 is withdrawn, the assembled damper may be removed from the die block 21, the sheet metal damper plate 23 being thus rigidly clamped upon the screw threaded stem IS.

The advantages of this method of attaching the sheet metal damper plate to the screw threaded stem are obvious, since with this arrangement, it is possible to use a stem formed of a gray iron casting which costs considerably less than a malleable iron casting.

By providing the outwardly diverging angular arms 22 upon the handle portion of the damper, it will be seen that the tips of these arms, which are the only part engaged by the thumb and finger in adjusting the damper, are located considerably further away from the hot damper than the usual handle construction in which the arms extend outward at right angles to the stem, thus permitting the operation of the damper without danger of burning the thumb or finger.

I claim:

The method of assembling a sheet metal damper plate having an opening surrounded by a frusto-conical flange shouldered at a point spaced from its edge, upon a stem having a pair of annular shoulders of differential diameters greater than the interior of the flange and a conical portion between said shoulders, which consists in forcing the flange over the smaller of said shoulders expanding the flange as it passes over the shoulder, and then contracting the flange upon the conical portion of the stem so that it is rigidly clamped upon the stem with its edge fitting tightly against the smaller shoulder and its shouldered portion fitting tightly against the larger shoulder of the stem.

MARTIN L. HUNKER. 

